JPS6081314A - Preparation of polyester yarn - Google Patents

Abstract

PURPOSE:To obtain the titled yarn having uniform fiber quality and thickness and level dyeing properties, by extruding a polyester containing inert fine particles with specific average particle diameter from a spinneret, cooling the yarn to a specific temperature, traveling it in a high-temperature hot atmosphere, winding it at high speed. CONSTITUTION:A polyester (e.g., polyethylene terephthalate, etc.) containing inert fine particles (e.g., silicon oxide, etc.) with 10-100mmu average particle diameter is melted and extruded from a spinneret to give yarn, which is cooled to <= the glass transition temperaure +70 deg.C, successively made to travel in a hot atmosphere kept at 200-400 deg.C, and wound at >=3,000m/min to give the desired yarn. An amount of the inert fine particles is preferably 0.1-1.0wt% based on the polyester.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a method for producing polyester #fiber. More specifically, in addition to improving the melt-spinning stability of polyester, we have developed a polyester main fiber that has excellent yarn quality, thickness uniformity, and level dyeing properties, and can withstand practical use using only the spinning process. It relates to a manufacturing method.

<Prior art> In melt-spinning polyester, it is possible to produce fibers with practically sufficient elasticity only in the spinning process by increasing the take-up speed, as disclosed in Japanese Patent Publication No. 35-3, for example.
Publication No. 104.

This is known from the Journal of the Japan Institute of Textile Science, Vol. 33, pages T2O8 to 'L''214T1, etc. According to these, for example, in the case of polyethylene terephthalate, when the take-up speed is about 5 ooo+++/min or more, the fibers obtained are completely oriented ( It is said that the result is similar to that of conventional drawn yarn) K.

However, if the take-up speed is increased, particularly at a speed of 5 tl 00 m 7 minutes or more, single fiber breakage and yarn breakage during spinning will significantly increase, resulting in a significant decrease in operability.

In addition, the resulting fibers also have the disadvantage of having a low initial Young's modulus and strength compared to fibers obtained by spinning at a conventional low material speed and drawing in a separate process. There are many problems in putting fibers to practical use.

On the other hand, in spinning partially oriented yarn, there is a method of controlling the orientation of spun yarn by providing a heating zone under the spinneret (% Publication No. 35-13156), in which the yarn spun from the spinneret is suctioned with fluid. Special spinning methods have been proposed, such as a method of suctioning with a device and then spinning the material with a material device (*Kokai No. 54-151611).
Not only is it merely intended to control the elongation (elongation) or improve the winding form, but it is not expected to have any effect on spinning stability.

However, the present inventor thought that the strength and elongation of the spun yarn could be improved by applying a heating element in the above-mentioned high-speed spinning at sooom/min or more, and various studies have confirmed this expectation. was completely betrayed, and furthermore, it was confirmed once again that the spinning stability was poor.

However, the above n11 method still has the potential to provide a yarn that can be put to practical use without adding a drawing step, so it is still difficult to abandon it.

Therefore, in order to further improve the spinning stability and fiber physical properties, the present inventor has developed various spinning conditions such as polymer viscosity, spinning temperature, Although various studies have been conducted regarding the spinning draft, cooling conditions, etc., it has not been possible to improve both spinning stability and fiber properties within the range of spinning conditions employed in operations.

<Objective of the Invention> The object of the present invention is to eliminate the drawbacks of such conventional methods, improve the spinning stability when melt spinning polyester, and improve the uniformity of yarn quality and thickness, as well as the level dyeing property. It is an object of the present invention to provide a method for producing polyester fibers which are excellent and can be used in practical use only by a spinning process.

<Solution Means> The present inventor eliminates fgt the drawbacks of the conventional method such as fc described above. We thought that it would be more effective to improve the molten polymer, and as a result of intensive studies from this point of view, we melt-spun a polyester containing fine inert particles, and spun 1-] gold. The present invention was achieved based on the discovery that spinning stability is improved and the strength and elongation of the resulting fibers are improved when the fibers are fed at high speed after passing through a heating zone installed below.

That is, the present invention provides a polyester spun yarn discharged from a spinneret (glass transition temperature of the polyester +7
0'C) and then the nuclear filaments were heated to 200°C.
After running in a heated atmosphere maintained at a temperature of ~500°C, when the spun yarn is fabricated at a speed of 3000 m/min or more, the average particle size of the polyester is 10~10
This is a method for producing polyester fiber, which is characterized by melting and discharging polyester containing inert fine particles of 0 mB.

The polyester referred to in the present invention has terephthalic acid as a main acid component and has at least 1114. glycol, preferably ethylene glycol.

The main target is polynisnal whose main glycol component is at least one kind of fluxing glycol selected from trinotylene glycol and natramethylene glycol.

It is also possible to use a polyester in which a part of the terephthalic acid component is replaced with another difunctional carboxylic acid component, and/or a part of the Klifur component may be replaced with the above-mentioned Glyfur, which is not the main component, or other dimer components. It may also be a polynis sprue slightly replaced with .

Examples of difunctional carbonic acids other than themphthalic acid used here include isophthalic acid, naphthalene dicarboxylic acid, diphenylenecarboxylic acid, diphenoxychetane dicarboxylic acid, β-hydroxyethoxybenzoic acid, and p-oxybenzoic acid. acid, 5-sodium sulpoinphthalate, 7
Aromatics such as divic acid, sebacic acid, I,4-cyclohexanedicarboxylic acid.

Examples include aliphatic and alicyclic difunctional carboxylic acids.

Examples of diol compounds other than the above-mentioned glycols include aliphatic compounds such as cyclohexane-1,4-dimetatool, iopentyl glycol, hisphenol A, and bisphenol S.

Examples thereof include alicyclic and aromatic diol compounds, polyoxyalkyshin dalicols, etc. Such polyesters may be synthesized by any method. For example, in the case of polyethylene terephthalate, it is usually a direct esterification reaction between terephthalic acid and ethylenebrifurt, or a Nisdel exchange reaction between a lower furkyl nisol of terephthalic acid such as dimethyl terephthalate and ethylene glycol. Glycol eneter of terephthalic acid and/or terephthalic acid are reacted with ethylene-J-hair hydroxide to form a low-1 combination. It is produced by a two-step reaction of heating and polycondensation reaction until the desired degree of condensation is reached.

Inert fine particles to be blended in the present invention include oxides such as silicon oxide, calcium carbonate, titanium oxide, and aluminum oxide, calcium phosphate, calcium hydrogen phosphate, and phosphate dihydrate. sium, sodium phosphate.

Phosphoric acid-hydrogen butryuno, sodium dihydrogen phosphate,
Phosphates such as potassium phosphate, potassium hydrogen phosphate, and potassium dihydrogen phosphate, and sulfates such as barium sulfate and calcium sulfate can be used, but silicon oxide is particularly preferred in terms of ease of handling.

In the polyester used in the present invention, inert fine particles are added in the production process of H-lyester, but after the inert fine particles are made into a water-dispersed sol, water is replaced with ethylene glycol, and ethylene glycol is added to the polyester used in the present invention. A dispersion is preferred. 5. Inert fine particles directly,
When dispersed in ethylene glyfur, there is a tendency for agglomeration to occur upon addition and formation of coarse particles. To prepare such an ethylene glycol dispersion of inert fine particles, first, the inert fine particles are dispersed in water to create a water-dispersed sol containing 20 to 30 i of inert fine particles.

Water and equivalent amounts of ethylene glycol are then added and heated to about 80° C. under vacuum under 10 ra+119 JJ in a rotary evaporator to evaporate the water and replace it with ethylene glycol. Then, if necessary, dilute with ethylene glyfur to adjust to the desired concentration.

Furthermore, a commercially available water-dispersed sol of inert fine particles may be used.1 Furthermore, the inert fine particles used have an average particle size of 10
~100 mμ is required. Here, when inert fine particles with an average particle size of less than 1Qmμ are used, even if the resulting polyester is melt-spun, the spinning stability is lacking, and the strength of the resulting fiber is low, and the elongation is low. Since it is large, it does not have enough strength and elongation to be used for practical use as it is. On the other hand, when inert fine particles having an average particle diameter exceeding 10011 μm are used, spinning stability cannot be achieved even if the resulting polyester is melt-spun.

Further, the astringency of the ethylene glycol dispersion of the inert fine particles is preferably 15% by weight or less. 0 degrees is 15 times @
If the limit is exceeded, agglomeration will occur during addition, single fiber breakage,
It tends to cause thread breakage.

The amount of such inert fine particles added to the polyester is preferably 0.1-1.0 wt.
! The amount is particularly preferably 0.3 to 0.8M.

If the amount added is less than 0.1% by weight, spinning stability and fiber physical properties (111) tend to be insufficient. Furthermore, if the amount added exceeds 1.0 weights, the number of aggregated particles increases, which tends to cause single fiber breakage and yarn breakage.

The polyester thus obtained is subjected to melt spinning,
In the melt spinning in the present invention, a heating atmosphere zone is provided below the spinneret, and after the spun yarn is heated,
It is necessary to move land at a speed of more than a minute.

That is, the spun yarn obtained by melting and discharging the polyester from a spinneret is cooled to a temperature lower than (Tg + 7oC), preferably to a temperature of ('l''g - 40'C) to (Tg + 40C)1. Tg is the glass transition temperature of the polyester forming the spun yarn.The spun yarn cooled to 5K is immediately heat-treated at an ambient temperature of 200 to 400°C by running through a heating atmosphere zone. The yarn temperature immediately before undergoing this heat treatment is (7g + 70
C), it is difficult to perform the heat treatment uniformly, and the homogeneity of the resulting yarn deteriorates. For this, ('l
'g +70°C), preferably (Tg +40°C)
) Heat treatment should be performed 1x5 at a lower temperature.

As the heat treatment means, a heating cylinder or a slit heater is used. In particular, a slit heater using infrared rays has better heating efficiency than other heat treatment means, and is most preferable as a heating treatment under spinning speed. This infrared gland slint heater is placed 50 to 150 cm in the direction of yarn travel.
It is possible to heat-treat the yarn uniformly in a short time in a relatively short heat-treating zone.

Infrared rays are generated by heating a rod-shaped or fill-shaped heater (electrical resistance heating element) above about 50o" cAI,
For example, by providing a heater in a spiral shape surrounding the running yarn and heating the heater to a temperature of about 500° C. or higher, the light can be easily projected onto the running yarn.

In general, the heating atmosphere temperature is such that the spinning pulling speed is relatively low (
aooo~sooom/min), the lower temperature (
200°C to 250°C), relatively high speed (soo
om/min), use a higher temperature (250°C to 400°C).
) is preferred. These temperatures may be appropriately set depending on the required yarn quality (strength, elongation, Young's modulus, boiling water absorption rate, etc.) K of the target polyester fiber. However, in any case, if the heating atmosphere temperature is less than 200°C, the draft rate in the atmosphere will be small, and the effect of improving yarn orientation and crystallization will be small, making it difficult to achieve the purpose of the present invention. On the other hand, at temperatures higher than 400° C. or in such an atmosphere, it is not preferable because it tends to cause melting effect and yarn breakage.

As mentioned above! , the yarn exiting the FJ zone is applied with a suitable finishing agent (oil agent) using a mailing roller or the like according to the requirements, and then transferred to a pair of godets IJ-ra or 1 and 57.
3000m/min or more from the switch button, preferably 500m/min.
0 M/min or more +7): ti u q- company l 1ro
c.? 7', -if! Ifll 3i Maka 3
00011+/min, the properties of the obtained yarn (strength).

elongation, initial modulus, etc.) are insufficient for practical use.

<Function> According to the method for producing polyester fibers having the structure of the present invention, the +15 polyester spun yarn, which is generally in a semi-molten state, undergoes molecular orientation by drafting, but at that time, the inert fine particles specified in the present invention When present in the system, such fine particles are KG between the polyester fibrils.
In order to fulfill the role of 11, molecular orientation can be made more plane, oriented crystallization can be enhanced, and the yarn ultimately obtained becomes a polytwin still fiber that can be put to practical use as it is.

<Effects of the Invention> As described above, the production method of the present invention enables stable spinning at material speeds of ft 5000 m 7 minutes or more, which conventionally involved extremely high internal dispersion, and improves uniformity and uniformity in the spinning process alone. Polyester fibers with excellent dyeability and poor properties such as strength, elongation, and Young's modulus that can be put to practical use as they are can be obtained.

Moreover, such polyester fibers also have extremely good heat setting properties in the edge process.

<Example> Next, the present invention will be explained in further detail by giving examples.

In the examples, the part is M, and (n) is the intrinsic viscosity determined from the value measured at 30° C. in an orn chlorophenol solvent.

In addition, the Ul value used for uniformity evaluation was commercially available Ust
It was measured using an Evenness Te5ter.

Examples 1 to 91 Comparative Examples 1 to 6 To 100 parts of dimethyl terephthalate and 0 parts of ethylene glycol, 0.025 mole of mankanese acetate was added to dimethyl terephthalate, and transesterification reaction was carried out while distilling off methanol at 150 to 250°C. I did this. At that time, the style was 10 weight i
The tethylene glycol dispersion was added at a reaction temperature of 200° C. so that the negative silicon oxide in the polyester reached the values shown in Table 1.

-x-7- After the completion of the teller exchange reaction, 25 parts of trimethyl phosphate and 75 parts of ethylene glycol were heated under reflux at 150°C for 5 hours in a closed system, and the glycol solution of the υ compound prepared on site was exchanged with trimethyl phosphate. It was added in an amount of 0.0307% based on dimethyl terephthalate.

After reacting for 10 minutes, 0.030 mol of antimony trioxide was added as polycondensation finance 1, and further a, 4 m:
1 tsp of datum dioxide was added, and the mixture was allowed to react for 20 minutes. Then, the obtained reaction product was transferred to a reactor equipped with a pressurizer and a glycol condenser, and the temperature was gradually raised from 230°C to 28 +1'C while gradually decreasing from normal pressure.
The pressure was shifted to 1ICM, and the polycondensation reaction was carried out under a vacuum of 1 Torr or less, and the obtained ester chips were melted in a bath at 290°C, then discharged from a spinneret, and the temperature was increased to 2
6℃.

Cooling air with a relative ω degree of 70 degrees is blown onto the spun yarn at a linear speed of 15111/min to cool it, and after the yarn is cooled to 90°C, the speed is collected in a ring-shaped kite, and then the yarn percentage is length 1
After passing through a 00 cm infrared heating slit heater (the air atmosphere is shown in Table 1), a finishing agent was applied using an oiling 1-1 roller, and the material was cultivated at the take-up speed shown in Table 1.

The spinnability and physical properties of the resulting yarn are also shown in Table 1.

Note that the yarn physical properties of the conventional drawn yarn are the values shown in ].

Level dyeing and spinnability were determined using the above conventional drawn yarn as standard. (In other words, the mark ○ indicates the above-mentioned drawn yarn quality, and the mark x indicates the quality) (
From Table 1, Examples 1 to 9, which are within the scope of the present invention, have good spinnability and the resulting yarn physical properties. The results were comparable to those of conventional drawn yarns.In other words, in Comparative Examples 1 to 6, which fall outside the scope of the present invention, both the spinning stability and the physical properties of the resulting yarns were unsatisfactory.

Claims (1)

[Claims] il+ The polyester spun yarn discharged from the spinneret is cooled to a temperature lower than (the glass transition temperature of the polyester + 70°C), and the yarn is subsequently maintained at a temperature of 200 to 400°C. After running the sauce in a heated atmosphere, 300
A method for producing polyester fibers, which comprises melting and discharging a polyester containing inert fine particles having an average particle size of 10 to +oomμ as the polyester when taking the fiber at a speed of 0.0111/min or more. (2) The ratio of inert fine particles to polyester is 0.1 to 1
．． A method for producing a polyester fiber according to Claim No. (1) ¥4 containing 0% by weight. (3) The polyester fiber according to claim 11 or claim 21, wherein the inert fine particles are silicon oxide.